1. Field of the Invention
This invention relates to an image production apparatus which includes an optical modulation apparatus of the one-dimensional type which uses, for example, a diffraction grating such that the diffraction angle of light is changed to modulate the light to project an image.
2. Description of the Related Art
An image production apparatus such as a projector or a printer is known wherein image light having one-dimensional image information is scanned by a light scanning apparatus and projected to an image forming member such as a screen or to print paper to form a two-dimensional image.
As one of apparatus for obtaining such a one-dimensional image, an optical modulation apparatus is known which uses a very small electro-mechanical device having an optical function, that is, a MEMS (Micro Electro Mechanical Systems) device.
Most of optical modulation apparatus which use a MEMS device are used for an optical switching system in a broad sense which controls the advancing direction of light or turns on/off light.
As one of types of such optical switching systems, an optical modulation apparatus of the diffraction grating type which uses a one-dimensional optical modulation device formed from a MEMS device having a function of a diffraction grating is known. An optical modulation apparatus of the type described is disclosed, for example, in Japanese Patent No. 3401250 (hereinafter referred to as Patent Document 1) and also in Japanese Patent No. 3164824 (hereinafter referred to as Patent Document 2).
If the optical modulation apparatus of the diffraction grating type is used to modulate light from a light source in accordance with image information or the like to project an image to a planar screen, a cylindrical screen, a wall face indoors or the like or scan the light on print paper or the like, then a two-dimensional image can be displayed or produced.
Where an optical modulation apparatus of the one-dimensional type such as of the diffraction grating type is used to form an image production apparatus in this manner, a modulation factor which provides a great variation in light amount can be implemented and display with a wide bandwidth can be achieved. Consequently, it is possible to provide an image production apparatus of a small size which operates with a low operation voltage.